Boiler



Sept. 25, 1951 c, T. DENKER ET AL BOILER s Sheets-Sheet 1 Filed Feb. 27, 1947 m T T S wwm j n n n 880 r vp w m1. R4 Mn 3% Qua w? AZ 2 3 w w Q Sept. 25, 1951 c. "r. DENKER ETAL' BOILER 3 Sheets-Sheet 5 Filed Feb. 27, 1947 rrrrt O-O G @-0 0 Patented Sept. 25, 1951 BOILER Charles T. Denker and John R. Moore, Chicago, Ill., assignors to The Calefactor Corporation, Chicago, 111., a corporation of Illinois Application February 27, 1947, Serial No. 731,218

3 Claims.

This invention relates to boilers and more specifically to boilers of the fire tube-water tube type.

It is a primary object of our invention to afford a novel fire tube-water tube boilerwherein the hot combustion gases used for heating the working fluid therein are caused to flow in substantially equal volume through, and over the outside surface of, the water tubes thereof.

An object ancillary to the foregoing is to construct a fire tube-water tube boiler in a novel manner whereby the hot gases, which flow over the outside surface of the water tubes for heating the water therein,.are caused to hover somewhat around the water tubes.

A further object of our invention is to afford a compact, efficient boiler of the previously mentioned type, and an object ancillary to this is to enable a boiler of relatively high heating capacity to be constructed in such a manner that it occupies relatively little floor space.

Another object of our invention is to construct a novel fire tube-water tube boiler wherein the headers and tubes are mounted at a substantial angle to the vertical, and an object ancillary to this is to afford a boiler wherein the combustion gases in rising therethrough, around the water tubes, not only tend to pass between the water tubes but also'at an angle therecross.

A further object of our invention is to afford a novel fire tube-water tube boiler wherein the water to be heated flows both longitudinally and transversely therethrough in good heat exchange relation with the combustion gases therein.

Yet another object of our invention is to afford a novel boiler wherein the water tubes and headers thereof may be readily and expeditiously cleaned or blown.

Further objects of our invention are: to so construct a novel fire tube-water tube boiler that access to the interior thereof may be readily gained for the purpose of cleaning the boiler, and the like; and to afford a novel fire tube-water tube boiler that can be readily and economically manufactured commercially.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show a preferred embodiment and the principles thereof and what we now consider to be the best mode in which we have contemplated applying those principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended,

claims.

In the drawings:

Fig. 1 is a front perspective view of a boiler embodying the principles of ourinvention;

Fig. 2 is a sectional view taken substantially along the line 22 in Fig.- 3;

Fig. 3 is a sectional view taken substantially along the line 3--3 in Fig. 1;

Fig. 4 is a sectional-view along the line 4-4 in Fig. 3;

Fig. 5 is a sectional view taken substantially along the line 55 in Fig. 3; 1

Fig. 6 is an enlarged detail sectional view taken substantially along the line 6-6 in Fig. 3; and

Fig. '7 is an enlarged detail sectional view taken substantially along the line '|'l in Fig. 3.

The boiler shown in the accompanying drawings. comprises a shell or housing 20 having a front wall 22, a rear wall 23, a top wall 25, a bottom wall 26, and two side walls 28 and 29. Each of these walls preferably comprises an outer panel 3| of a suitable material such as sheet steel and a lining 32 of any suitable insulating material such as, for example, magnesia. The lower end portion of the housing 20 is, in addition, lined with a suitable refractory material R such as fire-brick and comprises a fire box or lower combustion chamber L as will be presently discussed in greater detail.

A lower header 34, comprising an arm 36 and five legs 3'! projecting substantially perpendicularly therefrom in substantially parallel relation to each other, is mounted in the housing 20. The free end portions of the legs 31 are mounted in a recess 39 formed in the front wall 22, Fig. 3, and the arm 36 rests on brackets 4| which project inwardly from the rear wall 23, the arm 36 being held on the brackets 4| by a suitable fastening means such as U-bolts 43.

An upper header 45 comprising an arm 41 and five legs 48 projecting substantially perpendicularly therefrom in substantially parallel relation to each other, is mounted in the housing 20 above the lower header 34. The free end portions of the legs 48 are mounted in a recess 50 formed in the rear wall 23 and the arm 41 is mounted. on brackets 52, projecting inwardly from the front wall 22, and is held thereon by U-bolts 53.

As is best seen in Fig. 3, the lower header 34 and the upper header 45 are mounted in the housing 20 in substantially parallel relation to each other, and are both mounted therein at an angle to the horizontal with the front end portions thereof positioned above the rear end portions thereof.

A plurality of water tubes 55 interconnect corresponding legs 3'! and 48 of the lower header 34 and the upper header 45, and form watertight connections therebetween through which water may fiow from the header 34 to the header 4 5.

taken substantially An inlet pipe 51, through which water may be introduced into the lower header 34', Figs. 2 and 3, extends through the rear wall 23 of the housing 20 and is connected to the arm 35 of the header 34, and an outlet pipe 59, Figs. 3 and 4, through which hot water may flow from the up;

per header 45, extends through the top wall 25 of the housing 20 and is connected to the arm of the header 45. Thus, as is best seen in Fig. 3, it will be noted that water, in flowing through the boiler from the inlet'pipe 5'! to the outlet pipe 53 flows in a relatively zigzag course, flowing both transversely of the housing 20 and vertically therethrough.

A plurality of fire tubes 6! are mounted in the housing 20, each of the fire tubes Bl extending longitudinally through a corresponding one of the water tubes in spaced relation to the side walls thereof, and extending transversely through the legs 37 and 48 of the lower header 34, and the upper header 45, respectively. The connections between the fire tubes 6| and the header 34 and the header 45, respectively, are sealed by any suitable means such as, for example, welding to prevent the leakage of water therethrough.

It will be noted that the lower header 34 and the upper header 45 divide the interior of the housing 20 into three areas, namely, a fire-box or lower combustion chamber L, an intermediate combustion chamber M, and an upper combustion chamber U.

An exhaust duct Or stack 63 through which combustion gases may be exhausted to the atmosphere from the interior of the housing 2% extends through the rear wall 23 and opens into the upper combustion chamber U.

In the preferred form of the invention, as shown in the accompanying drawings, on is used for fuel and may be fed into the fire box L by any one of several types of units which are well known to the art,- such as, for example, the oil-burner unit 65, shown in Fig, 2, which comprises a nozzle 61 which projects into the fire-box L through an opening 68 in the front wall 22 of the housing 26, and through which a mixture of air and oil is fed by a blower 69 driven by a motor 10. I-Iowever, it will be noted that other suitable fuel and other types of fuel-feeding units may be used by those skilled in the art without departing from the purview of our invention and that the oil burner unit 65 is shown in the accompanying drawings merely by way of illustration and not by way of limitation thereto.

The legs 31 of the lower header 34, Figs. 4 and 7, are spaced relatively far apart so that a relatlvely free flow of hot gases, or other combustion products, is afi'o'rd'ed from the fire box L to the intermediate combustion chamber M, wherein it is in contact with the outer surface of the water tubes 55'; However, as is best seen in Figs. 4, 5, and 6, the legs 48 of the upper header 45 are considerably larger in cross section than the legs 31 of the lower header 34' and the spaces therebetween are considerably narrower than the spaces between the legs 31 so that the upper header 45 restricts the open area within the housing 20 and tends to retard the passage of combustion gases from the intermediate combustion chamber M to the upper combustion chamber U, exteriorly of the water tubes 55. For this purpose, we prefer to so construct the upper header 45 and so position it within the housing 29 that the total cross sectional area of the open spaces between the legs 48 and between the outer edge portions of the upper header 4'5 and the side walls 22, 23, 28 and 29 of the housing 20 is substantially equal to the total cross sectional area of the open spaces through the fire tubes 6!. In this manner the flow of hot combustion gases over the outside surface of the water tubes 55 is controlled so that it is substantially equal to the flow of hot gases through the inside of the water tubes. Therefore it will be seen that although the relatively open construction of the lower header 34 permits a relatively large volume of hot gases to fiow upwardly therethrough from the fire box L into the intermediate combustion chamber M, the upper header effectively restricts the flow of hot gases therepast into the upper combustion chamber U and thereby causes the gases to hover and circulate around in the intermediate combustion chamber M so that their contact with the outside surface of the water tubes is prolonged. 7 Also it will be noted that in flowing upwardly through the intermediate combustion chamber M the hot gases now at an angle across the water tubes 55 so that they are deflected and retarded thereby.

Two doors or removable panels 12 and 13 are mounted in the top wall 25 and the front wall 22, respectively, of the housing 20 and may be readily removed therefrom when it is desired to gain access to the interior. of the housing 29 for the purpose of cleaning it out, or the like.

Two clean out plugs 15 and 16, Fig. 4, are mounted in the end portions of the lower header and the upper header 45, respectively, and are readily accessible from outside the housing 20 through openings 18 and 19 in the side wall 28 thereof, two removable caps 8| and 82 being nor mally positioned in the openings 78 and 19, respectively, to protect the plugs 15 and 16.

Thus, from the foregoing it will be apparent that in the operation of our novel boiler, water is fed through the inlet pipe 51 into the arm 36 of the lower header 34 from which it flows through the legs 3! of the lower header 34 transversely of the housing 2b, at an angle to the horizontal and in good heat exchange relationship with the hot gases formed in the fire box L by the combustion of fuel fed thereinto from the fuel feeding unit 55. The water then passes upwardly at an angle to the vertical, through the water tubes 55, exteriorly of the fire tubes 6 I, from the lower header a: to the upper header 45, through which latter it again flows transversely to the housing 20, at an angle to the horizontal, and is exhausted therefrom through the outlet pipe 59.

The hot gases and other combustion products formed in the fire-box L by the combustion of fuel therein pass upwardly therefrom, part of the gases entering the fire tubes 61 and passing upwardly therethrough into the upper combustion chamber U, and the other part flowing upwardly through the relatively wide spaces between the legs 36 of the lower header 34 into the intermediate combustion chamber M in which they are retarded in their upward flow by the upper header 45 which, as previously explained, restricts the open space through which the hot gases may pass upwardly from the intermediate chamber M to the upper chamber U exteriorly of the water tubes 55, to substantially the same space as that through the fire tubes 6|, through which the hot gases may pass upwardly into the under combustion chamber U, interiorly of the water tubes 55. The restricting of the upward flow of gases from the intermediate chamber M, by the upper header 45, causes the gases to hover and circulate in the intermediate combustion chamber M and, thereby prolongs the maintenance of good heat exchange relationship between the gases and the outside surface of the water tubes 55.

Therefore, from the foregoing it will be apparent that we have provided a novel fire tubewater tube boiler wherein the flow of gases through the fire tubes and past the water tubes is controlled in a novel and expeditious manner so as to cause the gases to pass through our boiler in a highly efiicient heat exchange relationship with the water in the headers and in the water tubes.

Also our novel boiler is so constructed that the fiow of gases through the fire tubes and around the water tubes is controlled in such a manner that the fiow through these two paths is substantially equal in volume, and the fiow of gases exteriorly of the water tubes is not only in a longitudinal direction with respect thereto, but is also transverse thereto and somewhat turbulent.

Furthermore, it will be noted that our novel boiler is so constructed that the interior thereof may readily .be cleaned exteriorly of the water tubes, and that the water tubes and the headers may be readily blown.

Hence, while we have illustrated and described the preferred embodiments of our invention, it is to be understood that these are capable of variation and modification and we therefore do not wish to be limited to the precise details set forth, but desire to avail ourselves of such changes and alterations as fall within the purview of the following claims:

We claim:

1. A boiler comprising a housing having side walls, an upper header mounted in said housing and comprising an elongated arm and a plurality of substantially parallel legs projecting from one side of said arm in spaced relation to each other, said arm and legs being respectively spaced from certain of said side walls, a lower header mounted in said housing below said upper header and comprising an elongated arm and a plurality of substantially parallel legs projecting from one side of said last named arm in spaced relation to each other, said arm and said legs of said lower header being respectively spaced from certain of said side walls, a plurality of water tubes mounted in said housing in spaced relation to each other and interconnecting said upper header to said lower header, fire tubes having longitudinally extending openings therethrough extending through said water tubes, means for feeding water into said lower header, outlet means connected to said upper header, means for feeding fuel into said housing below said lowerheader for combustion therein, and outlet means connected to the upper end portion of said housing for discharging combustion products to the atmosphere, the total cross sectional area of the spaces between the legs of said upper header and of the open spaces between said upper header and said side walls being substantially equal to the cross sectional area of the openings through said fire tubes.

2. A boiler comprising a housing having side walls, an upper header mounted in said housing and comprising an elongated arm and a plurality of substantially parallel legs projecting from one side thereof in spaced relation to each other, said arm and said legs being respectively spaced from certain of said side walls, said upper header being positioned at an acute angle to the horizontal, a lower header mounted in said housing below said upper header and comprising an elongated arm and a plurality of substantially parallel legs projecting from one side thereof in spaced relation to each other, said arm and said legs of said lower header being respectively spaced from certain of said side walls, said lower header being positioned in said housing in substantially parallel relation to said upper header, a plurality of water tubes mounted in said housing in substantially parallel spaced relation to each other and interconnecting said legs of said upper header with said legs of said lower header, said water tubes being positioned in said housing at an acute angle to the horizontal, fire tubes having open spaces therethrough extending longitudinally through said water tubes and transversely through said upper header and said lower header, means for feeding water into the lower portion of said lower header, outlet means connected to the upper portion of said upper header, means for feeding fuel into said housing below said lower header for combustion therein, and outlet means connected to the upper end portion of said housing for discharging combustion products to the atmosphere, and means including said fire tubes and said upper header for directing combustion products from the lower end portion of said housing to the upper end portion thereof, the total cross sectional area of the spaces between the legs of said upper header and of the open spaces between said upper header and said side walls being substantially equal to the total cross sectional area of the open spaces through said fire tubes.

3. A boiler comprising a housing having side walls, an upper header mounted in said. housing and comprising an elongated arm and a plurality of substantially parallel legs projecting from one side of said arm in spaced relation to each other, said arm and legs being respectively spaced from certain of said side walls, a lower header mounted in said housing below said upper header, a plurality of water tubes mounted in said housing in spaced relation to each other and interconnecting said upper header to said lower header, fire tubes having longitudinally extending openings therethrough extending through said water tubes, means for feeding water to said lower header, outlet means connected to said upper header, means for feeding fuel into said housing below said lower header for combustion therein, and outlet means connected to the upper end portion of said housing for discharging combustion products to the atmosphere, the total crosssectional area of the spaces between the legs of said upper header and of the open spaces between said upper header and said side Walls being substantially equal to the cross-sectional area of the openings through said fire tubes.

CHARLES T. DENKER. JOHN R. MOORE.

REFERENCES CITED The following references are of record in the 

